Varistor ceramics of ZnO Bi 2O 3 TiO 2 Sb 2O 3 system have been fabricated by introducing pre fabricated ZnO seed grains with different size distributions respectively. The results show that the varistor properties we...Varistor ceramics of ZnO Bi 2O 3 TiO 2 Sb 2O 3 system have been fabricated by introducing pre fabricated ZnO seed grains with different size distributions respectively. The results show that the varistor properties were significantly influenced by the size of introduced seed grains, and introducing larger seed grains is more advantageous to the modification of microstructure and the improvement of varistor properties. The varistor properties were considerably improved with a moderately increased sintering temperature or time, whereas degraded apparently when the sintering temperature or time was excessively increased. Compared with the sintering time, the sintering temperature plays a more critical role in determining the varistor properties. By introducing pre fabricated ZnO seed grains into the original powders, low voltage ZnO varistor ceramics possessing the desired electrical properties have been produced with a sintering temperature of about 1 210 ℃ and a sintering temperature of 2～2.5 h. [展开更多
The development of low-voltage ZnO varistor ceramics containing TiO2 is presented in this report. The varistor properties of ZnO ceramics with different compositions were measured, and microstructure of the ceramics w...The development of low-voltage ZnO varistor ceramics containing TiO2 is presented in this report. The varistor properties of ZnO ceramics with different compositions were measured, and microstructure of the ceramics was investigated by XRD and SEM. The results show that the addition of TiO2 is beneficial to the decrease of varistor voltage (V1mA). whereas it leads to the recession of nonlinear coefficient (α) and leakage current (lL). The varistor properties of ZnO ceramics containing TiO2 can be effectively improved by introducing moderate amount of pre-fabricated ZnO seed grains. The behaviors of TiO2 and seed grains, as well as the mechanisms by which TiO2 and seed grains influence varistor properties, are discussed.展开更多
文摘Varistor ceramics of ZnO Bi 2O 3 TiO 2 Sb 2O 3 system have been fabricated by introducing pre fabricated ZnO seed grains with different size distributions respectively. The results show that the varistor properties were significantly influenced by the size of introduced seed grains, and introducing larger seed grains is more advantageous to the modification of microstructure and the improvement of varistor properties. The varistor properties were considerably improved with a moderately increased sintering temperature or time, whereas degraded apparently when the sintering temperature or time was excessively increased. Compared with the sintering time, the sintering temperature plays a more critical role in determining the varistor properties. By introducing pre fabricated ZnO seed grains into the original powders, low voltage ZnO varistor ceramics possessing the desired electrical properties have been produced with a sintering temperature of about 1 210 ℃ and a sintering temperature of 2～2.5 h. [
基金Funded by the science fund of Wuhan University of Technology.
文摘The development of low-voltage ZnO varistor ceramics containing TiO2 is presented in this report. The varistor properties of ZnO ceramics with different compositions were measured, and microstructure of the ceramics was investigated by XRD and SEM. The results show that the addition of TiO2 is beneficial to the decrease of varistor voltage (V1mA). whereas it leads to the recession of nonlinear coefficient (α) and leakage current (lL). The varistor properties of ZnO ceramics containing TiO2 can be effectively improved by introducing moderate amount of pre-fabricated ZnO seed grains. The behaviors of TiO2 and seed grains, as well as the mechanisms by which TiO2 and seed grains influence varistor properties, are discussed.
